Start making a simple program in which we in assembly code using PIC 16F877A to turn on and off an LED by pressing a button as shown in the diagram. We will use two ports of the PIC 16F877A, port B and port D, declare the B port as input and the D port will be configured as an output. In the graph we can see that the pin RB0 is set button and a resistor in a pull-up configuration, when you are not pressing the button it gets a high (5V) to the RB0 input and when pressed he gets a level low (0V). In the output RD0 to turn on the led its output should be at a low level so when developing the program in assembler we test the pin B0 and if a high level put a high value on the output RD0 that will keep off LED, otherwise put a low value on the output RD0 which will cause the LED lights. ASSEMBLER PROGRAM FOR PIC 16F877A To make the program use the MPLABX 2.0 Open the IDE MPLABX program. We click file, select New Project ... In window "Select Project" emerging select "Microchi...